When N,O-diacylated 2-aminophenols that have different acyl substituents on
nitrogen and oxygen are treated with p-toluenesulfonic acid in refluxing x
ylenes, mixtures of benzoxazoles are produced. The major product is the ben
zoxazole in which the substituent at the 2-position is derived from the acy
l group on nitrogen. This product may arise from an unusual case of acid-me
diated neighboring amido-group assisted hydrolysis.